Pre-charge pressure of a hydraulic accumulator needs to be periodically checked after installation in a hydraulic system to ensure operational health of the accumulator. Typical solutions for detecting the accumulator health involve connecting a gas pressure gauge and/or a modular kit to a gas valve of the hydraulic accumulator, when the machine is stopped and the fluid in the hydraulic accumulator is not pressurized. The gas pressure gauge provides a reading of the pre-charge pressure. Depending on such readings, the hydraulic accumulator is either re-charged or completely overhauled or replaced. Hence, typical solutions required physically connecting the hydraulic accumulator to the pressure gauge. However, the accumulator can be located on a machine such that it is difficult to access and couple the gas pressure gauge.
In one example, German Patent Number DE102005052640 relates to a method involving determination of a difference in accumulator volume using a flow regulator with constant adjustable flow rate and an actuating valve with preset response time. The method also involves determination of pressure values before and after the fluid withdrawal from a hydraulic accumulator using a pressure sensor based on its recalled calculated accumulator volume at an empty state.